


Shuuya's Theory of Revenge

by Aviantei



Category: Kagerou Project
Genre: Angst, Based on a Vocaloid Song, Bullying, But one that's not part of KagePro, Gen, One Shot, Sociopathic Shuuya, Suicide
Language: English
Status: Completed
Published: 2019-10-03
Updated: 2019-10-03
Packaged: 2020-11-23 00:16:08
Rating: Teen And Up Audiences
Warnings: Major Character Death
Chapters: 1
Words: 4,530
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20883023
Author URL: https://archiveofourown.org/users/Aviantei/pseuds/Aviantei
Summary: [One Shot] "Are you okay, Onee-chan?" The question is so sudden that Ayano jumps and drops her pencil under the table.





	Shuuya's Theory of Revenge

**Author's Note:**

> This one shot was originally published on September 9, 2014. One of my friends at the time had seen the PV for IA's "Revenge Syndrome" and mistook it for a part of Kagerou Project. So I wrote a one shot with that. Man, 2014 me was super edgy.
> 
> This fic includes instances of bullying and suicide, so please read with caution.
> 
> I hope you enjoy.

**Shuuya’s Theory of Revenge**

By: Aviantei

A _Kagerou Project_ One Shot

* * *

“One last thing before your lunch break,” the teacher calls out. The rest of the students are already restless, some on the edge of jumping out of their seats. A few others have almost dozed off in their chairs, but look up at the teacher’s words. It’s been a long lecture, and everyone’s probably ready to be done for the day, let alone for lunch. Ayano manages to still herself from grabbing her bento, but can’t help but steal a glance at the boy beside her.

As always, Shintaro is gazing out the window. From what she can see of his reflection, he looks as bored as ever.

“I have the results of the last test you all took, so come up whenever I call your name. After you get your test you’re free to go. If you’re eating lunch in the classroom, please keep the noise level down until everyone gets their tests. First is Ando…” The teacher begins to go through the list of names, handing back their tests. Several students bolt for the door once the paper is in their hands, reducing the amount of people in the room bit by bit.

Ayano is grateful.

“Kisaragi,” the teacher says. Shintaro doesn’t respond. “_Kisaragi_,” he repeats. This time the boy in question does stand up, walking slowly to the front of the classroom. A few of the other students who clearly want to just get their grades and get out of here glare as Shintaro takes his time. He doesn’t care though, and Ayano giggles.

The list goes on from there, and Ayano peeks at Shintaro’s desk. Before she can see his grade, however, the teacher says, “Tateyama.” The girl stands up, trying to hide her nervousness. She knows she hasn’t done very well, and it feels like everyone in the class knows it by now. It doesn’t bother her much, but the collective gaze that seems to focus on her does.

_46_. The number in red ink that the top of the paper is clear, says everything that needs to be said. “Tateyama,” the teacher repeats anyway, keeping his voice low. “You do know that if you’re struggling, you’re allowed to ask for help. You’re friends with Kisaragi, right? Why not ask him? Or your father? I normally wouldn’t say anything, but I’ve heard from the rest of the teachers. If you keep this up, you’re not going to be able to get into a good high school.”

Ayano clutches the paper a little too hard in her hands, crinkling the contents of the exam but not its results. She _knows_. Even without practically every one of her teachers reminding her, she knows. The sad thing, this is the best she can manage _with_ Shintaro’s assistance, and everything just happens to still escape over her head. With her mom gone, there’s no point in asking her father either.

“I understand, Sensei. I’ll try that,” Ayano says. She goes back to her seat, and Shintaro gives her a curious glance. Ayano laughs a little and smiles, showing him her score. “You know how I am. This is about what I expected to get anyway, so don’t worry about it.”

“Your score’s improved, at least,” Shintaro says. It’s true, even if it’s only been a few points increase since the last one. At this rate, even Ayano knows she probably won’t be able to graduate middle school. “If we keep studying together, I’m sure that you’ll do even better next time.”

He’s trying so hard to sound encouraging that Ayano pretends she doesn’t notice when Shintaro hides his _100_ underneath his sleeve.

* * *

Ayano separates herself from Shintaro at the end of the day, claiming a need to use the restroom. Instead, she’s racing to the shoe lockers, trying to get there before anyone else does. Sure enough, there are tacks inside her shoes again, and she carefully dumps them out before changing. She wants to wait for Shintaro, to walk home with him, but knows it’s not a good idea to wait.

She’s almost out the door when the call of “Tateyama-san!” reaches her ears. Ayano flinches, hesitating in the doorway, taking away her opportunity to escape. She knows that she should still leave, but can’t bring herself to be rude about it. Against her better judgment, she turns back around.

“Why don’t we go out to eat together, Tateyama-san?” Sugawara Haruko says. She smiles, taking her own tack free shoes and changing them without having to worry. Ayano feels a small pang of jealousy, but forces it to go away. “There’s a café that serves delicious milkshakes that’s not too far from here. Shall we go?”

Ayano knows she shouldn’t. She knows by now what kind of person Sugawara is, knows how this is going to end. Ayano knows she should tell someone, too, but she never does. She never does anything to stop it, only does what’s polite and smiles and says “Yes.” Maybe it’s walking into situations where she knows that she’ll be hurt that really makes her stupid and not her test grades.

Within the next half an hour, Ayano is sitting across from Sugawara, an untouched milkshake in front of her. It does look good, and Sugawara seems to be enjoying hers, but Ayano’s stomach is too filled with knots to even consider taking a drink. At least this café provides take-home cups, so it won’t go to waste.

“Sorry for intruding, but I couldn’t help but overhear Sensei earlier when we were giving back tests,” Sugawara says. It’s a believable enough excuse, considering Sugawara _does_ sit in the front row, but Ayano knows better. Her classmate is nowhere near as good of a liar as her youngest brother is. “Tateyama-san, are you still struggling with the material? I’d be happy to help you out if you need it.”

Ayano shakes her head. Sugawara raises an eyebrow over the straw in her mouth. “I have Kisaragi-kun to help me out,” Ayano says. “I wouldn’t want to bother anyone else more than I need to.”

“Even if you’re bothering Kisaragi-kun?” Ayano winces at the words, but tries not to let them get to her. Surely Shintaro doesn’t think of her that way, or he would have said something. Surely he had wanted her as a friend, even if he was reluctant at first, right? “He’s always been a loner until you started talking to him, Tateyama-san. I know it’s a good thing that’s he’s opening up, but I can’t help but feel like he doesn’t want anyone around. I can’t help but wonder why you made friends with such an antisocial person…”

For the first time, Ayano frowns, and it has nothing to do with feeling sorry for herself. She tries really hard not to let these things show, but there are very few things she won’t tolerate to the extent of actually saying something about it. One of them is insults about or bad things happening to her family. The other…

“Your problem is with me, right, Sugawara-san?” Ayano asks. There’s venom in her voice and it scares her. She keeps a hold of it for a little bit longer. “If that’s the case, then leave Kisaragi-kun out of it.” Because Shintaro doesn’t deserve that, just because he’s her friend; because Shintaro’s her favorite person, because Shintaro _saved_—

Sugawara’s eyes narrow, and Ayano’s confidence takes the intended hit. “Don’t go and start making demands,” the other girl says, causing Ayano to recoil into the back of her seat. “It’s bad enough that you go around inconveniencing others. But you’re right, so I’ll leave Kisaragi-kun out of it for now. Let’s focus on the real point shall we?

“Tateyama-san, I really am just trying to help. You don’t have the grades to keep things up in school, and you’re not gonna be able to follow Kisaragi-kun around forever. So don’t you think it’ll be easier if you just quit now and get it over with?”

Ayano closes her eyes, not wanting to look at the expression on Sugawara’s face. Ayano _knows_ what she’s being told is true, and doesn’t need it reiterated any more than she needs the teacher’s words, especially not sugar coated like this. Really, it would be better if they just came out and said it, because their being indirect just makes it hurt all the worse.

_Because I’m stupid._

There’s no way that she can deny it. She doesn’t even try to. She didn’t get either of her parents’ academic aptitude for whatever reason. It’s really not so bad, because she’s seen the burden that being smart can put on others when they have too much of it. So Ayano tries not to let it bother her and just accepts that she’s stupid and that’s the way that it’s always going to be.

So why does it seem to matter so much to Sugawara?

Ayano listens, hoping she’ll understand. That’s the other part of the reason why she never runs away, because she wants to try and understand. Even people who have a hard time talking with others still end up communicating their thoughts, even unintentionally. That’s something Shintaro doesn’t know that he helped Ayano learn.

Despite her best efforts, not understanding after so long just makes Ayano feel much, much worse.

* * *

Whenever Ayano finally makes it home, she has managed to finally put a smile on her face, even if it is a bit forced. Even so, it’s better than there being no smile at all, especially whenever she walks into the living room and comes face to face with her siblings, who all end up asking about her day.

So of course she smiles. Of course she tells them she’s fine. They’ve all already lost their mother and their father just locks himself up, researching every moment that he’s not at work. When it comes down to it, Ayano, Shuuya, Tsubomi, and Kousuke are the only ones living in this house anymore, and the name _Tateyama_ written on the gate by their mailbox is just one big giant lie.

Ayano wishes she were a bit smarter, for their sake. For whatever reason, their parents decided to home school the other three—presumably to apply to their individual needs due to their _lack_ of conventional schooling before adoption. And while Ayano isn’t jealous, she just doesn’t know what to do since neither parent is around to continue the role anymore. Her siblings have just been doing individual progress on their workbooks for the past month, and Ayano doesn’t have the capacity to help them when they get stuck.

It’s when they’re all sitting around the table—Shuuya, Tsubomi, and Kousuke all applying varying levels of diligence to their workbooks and Ayano attempting to focus on her own homework—that Shuuya asks, “Are you okay, Onee-chan?”

The question is so sudden that Ayano jumps and drops her pencil under the table. When she’s back from the retrieval, three pairs of eyes are on her—eyes that were once afraid of being red—meaning to plea, but somehow demanding an answer. Shuuya’s always been sharp, and his suspicion is all the evidence that the other two need to think that something’s wrong.

“I’m fine, just tired,” she says. The answer is halfway true. Shuuya pouts at her a little, still pulling off the childish expression despite his start into puberty. Ayano reaches out a hand to ruffle his hair, and he doesn’t complain. “This math problem’s just really hard. Why don’t we take a snack break and see if that refreshes our brains a little, okay?”

Sometimes Ayano wonders if Shuuya can tell. After all, the boy is an exceptional actor, even if she can see through him most of the time. Maybe he can see through her lies, too.

If he can, he doesn’t show it. Shuuya smiles and runs towards the kitchen, challenging his siblings to a race. Taking his nonchalance as reassurance, Tsubomi and Kousuke chase after him, their footsteps echoing down the hall to the kitchen.

Ayano puts a hand to the scarf that is supposed to make her a hero and follows.

* * *

Ayano doesn’t encounter Sugawara again until the results of the next test come out. This time, the _37_ is tucked into her bag, and there are no warning words from the teacher. Ayano attempts to leave with Shintaro, but one of the girls who’s supposed to be on cleaning duty that day has to leave for a family emergency, so of course Ayano is the one that gets volunteered into the position. She doesn’t want to hold Shintaro back, so she lets him go ahead.

It’s a mistake and she knows it. So Ayano tries to leave as soon as possible without rushing her work. The problem happens when Sugawara gives her an invitation that Ayano declines. Instead of just being let go, Ayano finds herself being pulled along with Sugawara and her friends, a red mark on her cheek from where she gets pushed back into the group.

The wound doesn’t hurt as much as the words do.

She’s able to pass it off at home and at school—“I’m just a klutz, so I tripped and hit my head off a desk”—and everyone believes her. No one seems to think Sugawara’s responsible, especially since the girl comes and asks Ayano if she’s alright the very next day. So no one’s going to think that Sugawara’s behind the rest of the bruises and cuts, either.

Of course, she doesn’t cause all of them. Unlike Ayano, Sugawara has a lot of friends, and they all seem to be just as clever. They can trip and bump into Ayano in crowded hallways and no one notices. Ayano wishes they were accidents, so that’s why she says they are.

Even so, she doesn’t know how much more she can take. It’s stressful, but she doesn’t know who else to tell. Everyone will just worry, and she doesn’t want that. Ayano is supposed to be the strong one, the caring big sister, the supportive best friend. If she’s not okay, then who are they going to rely on? If she breaks down, who will they turn to? There’s no time to get depressed over decreasing numbers in red ink.

There’s hardly time to cry, but she does anyway.

* * *

Shuuya sits around at night, leaving an illusion behind in his bed so that his family thinks he’s in bed. He doesn’t like using his power to lie to them, but sometimes he just can’t fall asleep as quickly as he should. Especially not with how things have been for his big sister lately.

Sure, Ayano smiles. But it’s not really her smile. Even when she’s eating dinner with them or helping them with homework or watching a movie she likes, Ayano isn’t really smiling. It’s close to her smile, but it doesn’t reach her eyes, doesn’t ring true inside her laughter. It’s only gotten like this recently, and it started only a little bit before Ayano started coming home with bruises.

Most of them are able to be hidden under her school uniform, but they’re still there. Some of them are on her hands, some of them peek out under her sleeves when she stretches. Others end up revealing themselves when Ayano receives a hug or bumps against something and winces. In the end, the bandages and medicine that get picked up on trips to the store are evidence enough.

The worst part is that Ayano hasn’t said anything about it, just keeps on smiling. Shuuya wants to ask, but he never builds up the courage to do so. Besides, it seems like this is something Ayano wants to keep secret. Just because he notices doesn’t mean that Tsubomi and Kousuke do. There’s no reason to bring it up in front of them, and there’s really no way to talk about something that makes Ayano cry without alerting the others.

Even if he did ask, would she answer him? Ayano’s always been the best older sister he can imagine. And when it comes down to it, sometimes caring for other people means that you lie to them, so that the truth doesn’t hurt them. Even if Shuuya presented all the evidence that he has, would Ayano tell him? Maybe. Would she want him to do anything about it?

Absolutely not.

Regardless, Shuuya can’t just accept that. This isn’t something that Ayano should have to handle on her own. Shuuya doesn’t even think that she _can_ handle it on her own. He can’t tell anyone else, though, because Ayano doesn’t want that. So the only thing left to do is investigate and see where that gets him.

He has to do something, after all.

He can’t just do nothing.

Because he loves her.

* * *

Shuuya’s able to slip out of the house fairly easy without Tsubomi or Kousuke questioning it. Sure, he should probably put some work into his homeschooling, but finding out what’s happening with Ayano seems infinitely more important. Shuuya doesn’t really have any ambition to do something with academics anyway.

At first he considers just making himself invisible the whole time, but that’s too risky. After all, if someone bumps into him, that’ll just blow his cover. So Shuuya takes on the guise of a student, easily avoiding conflict and pulling out his invisibility mask once he takes up station behind Ayano’s seat in the classroom.

For a while, everything seems fine. Ayano goes through school life as Shuuya expected her to: doing her best to keep up with the notes on the board, talking to Shintaro in the seat beside her when breaks occur. During lectures, Shuuya finds himself able to keep up with most of the material, and it occurs to him that he and the others have been studying a few years beyond their age level at home.

It’s no wonder why Ayano sometimes hesitates whenever they ask for help.

At lunch, Shuuya realizes that he hasn’t planned this out as well as he would have liked, and that he seems to be missing food to eat. At least Ayano has planned to pick up her food from the school store, giving Shuuya a chance to resume his student guise and pay for his own lunch with the meager pocket change he has.

This pattern continues for a few days, and Shuuya begins to wonder if he’s misinterpreted the situation. The only thing that convinces him to keep going is that look on Ayano’s face, the one that isn’t her smile. There _has_ to be a reason for it, and he’s going to find it.

Within the next week, he does.

For some reason, he never considered the idea of bullying, but now it seems so painfully obvious. How else would Ayano get hurt like that? Why else would she be so sad? Ayano thrives off of positive interactions with others. Of _course_ being tormented by others is poison to his sister’s cheerful smile.

And it’s over as something as trivial as her grades, too. So what if Ayano isn’t at the top of her class? She always does everything she can to help others. She helped save Shuuya—helped save all three of them—convinced them that they weren’t monsters. She would never look down on another person for not being as good at something as they could be.

_She’s a million times—no, an _infinite_ amount of times—better of a person than you are._

Despite thinking that, Shuuya finds that he can’t do anything. Right when his sister needs him—_to be a hero_—Shuuya freezes. He can’t even bring himself to drop his mask because it’s such a defensive item by now. He can’t close his eyes. So Shuuya watches as his Ayano gets bullied for who knows how many times and walks away with a scrape on her cheek and a bruise on her elbow.

Shuuya almost cries when Ayano gives them the usual lie over dinner. He almost hurts himself to make up for the fact that he didn’t do anything to save her.

This entire thing has made Ayano a liar.

He doesn’t want her to have to endure that.

_This has to stop_.

* * *

It’s almost scary how quickly the plan comes to him, how easily. If the problem is bullying, then it just needs to come down to making them regret it. Shuuya is going to be a hero, but it’s going to be a secret _(another lie)_. If Ayano doesn’t want any of them to know about it, he’ll keep that secret. Besides, it will be easier to get revenge on them if he looks like someone who doesn’t exist.

This isn’t the first time he’s made himself look like a girl, but it’s the first time he’s actually going to do something with it. The first time he did it, it was more of a joke, just to see what he would look like. Kousuke got a laugh out of it at least. He tries to avoid it, though, considering how much more it makes him look like his mother.

_How terribly fitting…_

From there, he just needs to learn a bit more about his adversaries—the girls that have been harassing Ayano. He spends his time invisible, learns what they’re like. He mainly focuses on Sugawara, but having a little extra ammunition certainly isn’t a downfall.

It takes some consideration, but Shuuya eventually decides to head straight to the root of the problem. One day he follows Sugawara to the shoe lockers, then slips by her. After that, he stands in the doorway, the mask of his female self firmly in place, and smiles when his target approaches.

“How do you do, Sugawara-san?” he says, and his voice manages to come out sweet through the mask, even when all of his hate is seething inside of him. “Could I ask a favor?”

He plays himself off as a prospective student, asking to be shown the way to the music club room to meet up with a friend. Sugawara is hesitant at first, but ultimately agrees. Her pleasant public persona is almost as secure as Shuuya’s is, except it breaks whenever he corners her in an empty classroom and unloads every psychological attack he can think of on her.

Shuuya doesn’t remember half of what he’s said. All he knows is that the time he’s spent around these girls is enough to figure out their insecurities, and he _exploits_ them. He doesn’t stop until he’s sure that Sugawara’s crying, and even then he keeps going. He wants to hurt her like she’s hurt Ayano. He wants to physically harm her, but can’t bring himself to do it. Once he’s out of breath, he manages to let out one more sentence before he leaves, becoming invisible until he makes it to his front door.

“Stay away from Tateyama Ayano,” he says.

It’s the voice of his mother.

* * *

When Ayano realizes that Sugawara hasn’t come to school for a while, she starts to get a little worried. She really shouldn’t, considering everything Sugawara has done to her, but Ayano is a caring person at heart. Sugawara is her classmate, and she’s more than likely ill. It’s only human instinct that she’s concerned.

Admittedly, though, it does make things easier. In a few days, the next test results come back. Even if the number is as low as always, the lack of Sugawara’s presence makes Ayano feel less worried. Even when the group of girls still attempts to corner her after school, Ayano finds it easy to refuse, and she makes it home without any troubles.

Yamada doesn’t show up the next day. The rest of Sugawara’s group begins to taper off, either becoming absent or showing up present and obviously shaken. Aoki is the only one who isn’t affected, and Ayano is horribly worried for her. So when the girl goes to head home, Ayano follows. She loses track of her at first, but finds her safe in the art room. Ayano almost thinks she’s over reacting, but then _the_ _girl_ shows up.

She’s beautiful, and Ayano freezes in the gap between the door and its frame that she’s been looking for. The girl approaches Aoki, her long sandy blonde hair flowing behind her, contrasting against a hoodie that looks all too familiar. And then that girl is talking, her pretty face twisted by the words she’s saying, the ones that match perfectly with her glowing red eyes.

_No._

Ayano tries to tell herself that this isn’t happening, but she can’t manage it. She turns around, her back pressed against the wall in an attempt to remain upright. It doesn’t work, and Ayano finds herself sinking down to the floor, uncaring, sobbing. She tries to get ahold of herself, because maybe she can _stop it_. This _is_ her little brother after all.

She stands up, legs shaking. She opens the door to the art room, prepared to say something, but the words fail to come out of her mouth. Aoki is gone. The window is open. And Shuuya—Shuuya as a girl, pretty as can be—is standing there in the doorway, smiling, his eyes still glowing. He notices that Ayano is about to fall over again and catches her, the illusion shattering with the contact.

“It’s okay, Onee-chan,” he says, and his voice is back to normal. It’s soft, soothing. He’s not lying, either, and that only makes it even worse. “It’s okay because I became a hero for you.”

Ayano doesn’t know what she’s doing, but she somehow breaks out of Shuuya’s grasp. Her legs still support her, somehow, even though her eyes are filled with tears. This wasn’t what she wanted. Sure, she didn’t want to be bullied, but she never wanted anyone to die because of it. She wanted her siblings not to feel bad about themselves, not for Shuuya to become this—

_Could it be… that I wasn’t a good older sister after all?_

Ayano screams.

* * *

Ayano screams and it’s terrible, leaving Shuuya stunned. Without warning, she runs to the window, the one that Aoki just threw herself out seconds before, and for a terrifying moment she just stands there. Shuuya just stands there, too, because this is the _fourth floor_ and it means nothing if some bully jumps out, but if Ayano, _if Onee-chan_—

“Onee-chan, wait!”

It’s too late. Even running across the room at top speed isn’t enough to catch her. For a moment, Shuuya has hope—and then the fabric of her scarf slips away from his grasp, fluttering in the wind as it follows Ayano down. He can’t close his eyes. The sound is too far away to be heard, but he can imagine it far too well. It feels like a nightmare.

“Onee-chan?” he whispers. There’s no way she’s be able to pick up on that sound, but he hopes, because she’s his _big sister, she’s supposed to—_

* * *

There are two corpses below the window of the art room.

Both of them are Shuuya’s fault.


End file.
